A slide rail is utilized as a device for guiding linear movement or curved movement of a movable object such as a table. As disclosed in, for example, Patent Document 1 listed below, a general slide rail comprises: an outer rail attached to a fixed object; an inner rail attached to the movable object such as the table which is drawn out from the fixed object; and an intermediate rail which slides in a back-and-forth direction with respect to the outer rail and has upper side and lower side sidewall portions that hold the inner rail from an up-and-down direction. Moreover, in this kind of slide rail, ball bearings (rolling elements) are disposed between the outer rail and the intermediate rail and between the intermediate rail and the inner rail, and each of the rails performs a sliding operation smoothly due to the ball bearings (rolling elements) disposed between each of the rails. Furthermore, each of balls configuring the ball bearings (rolling elements) is configured so as not to become displaced from between each of the rails, by a ball retainer (cage).
However, the slide rail represented in Patent Document 1 is a limited type in which the balls do not circulate unlimitedly, hence there was a case that a malfunction due to misalignment of the cage easily occurred.
Accordingly, in this kind of technical field, a movement-guiding device called an unlimited circulation type linear guide has been employed in order to overcome the malfunction due to cage misalignment. For example, known as a conventional movement-guiding device employing an unlimited circulation type linear guide was a movement-guiding device in which two sets of linear guides are prepared and blocks capable of back-and-forth linear movement with respect to rails configuring the linear guides are installed so as to be back-to-back via an intermediate member, whereby relative linear movement of the rails and the intermediate member can be performed. Such a movement-guiding device makes it possible to stably guide movement of a long stroke.